The reductive ring opening of phthalan and isochroman in a 8 mmol scale process, using a small excess of lithium (1.35 equiv) and a substoichiometric amount of DTBB (3 mol%), leads to functionalised organolithium compounds, which after reaction with (-)-menthone as electrophile followed by hydrolysis with water, gives the corresponding diols in good yields with high stereoselectivity. Dehydration of these diols leads to the corresponding oxygen-containing heterocycles, which are homologous of the starting heterocycles.
使用过量的
锂(1.35当量)和次
化学计量的二
叔丁基二硫(3摩尔%),在8毫摩尔规模下进行
酞喃和
异色满的还原开环反应,得到功能化的
有机锂化合物。通过与
(-)-薄荷酮作为亲电试剂反应,然后用
水进行
水解,可以高产率、高立体选择性地获得相应的二醇。这些二醇的脱
水反应生成含氧杂环,它们是起始杂环的同系物。